Cinnamon
Cinnamon (in Hebrew “קינמון”) is made from the inner bark of trees of the Cinnamomum genus, and it is one of the oldest spices in the world — it is mentioned in the Hebrew Bible, was traded in ancient Egypt, and was among the most valuable goods of the ancient world. Today it is found in almost every kitchen, and in recent years it has drawn research attention mainly in connection with blood sugar control.
The most important point in this article is not a benefit but a distinction: two substantially different products are sold under the name “cinnamon” — Ceylon and cassia — and they differ in their content of a substance that can harm the liver. Most of the cinnamon sold in Israel and around the world is cassia.
Nutrition facts
Cinnamon is eaten in small amounts, so its direct nutritional contribution is limited. Per teaspoon (2.6 grams) of ground cinnamon:
| Component | Amount | % daily value |
|---|---|---|
| Calories | 6 kcal | — |
| Carbohydrates | 2.1 g | — |
| Of which fiber | 1.4 g | 5% |
| Of which sugar | 0.06 g | ~0% |
| Protein | 0.1 g | — |
| Manganese | 0.4 mg | 17% |
| Calcium | 26 mg | 2% |
| Iron | 0.2 mg | 1% |
| Vitamin K | 0.8 mcg | 1% |
An important point: cinnamon contains almost no sugar — 0.06 grams per teaspoon. Cinnamon is perceived as sweet because our brains associate its aroma with sweet pastries, but the spice itself is almost completely sugar-free. That is why it is an excellent tool for adding a sense of sweetness to porridge or yogurt without adding sugar.
More than two thirds of the carbohydrates in cinnamon are fiber, and it is especially dense in polyphenols relative to its weight — on antioxidant measures it ranks among the highest foods in the world. But remember that we are talking about an intake of just a few grams.
Ceylon vs. cassia cinnamon — the critical distinction
| Ceylon (C. verum) | Cassia (C. cassia) | |
|---|---|---|
| Origin | Sri Lanka | China, Indonesia, Vietnam |
| Nickname | “True cinnamon” | “Regular cinnamon” |
| Appearance | Multi-layered roll, papery and brittle | A single thick bark, rolled into a hard stick |
| Color | Light, tan-brown | Dark reddish-brown |
| Flavor | Delicate, sweet, floral | Sharp, spicy, intense |
| Coumarin content | Negligible (~0.017 mg/g) | High (~2–4 mg/g) |
| Price | 3–5 times more expensive | Cheap |
| Availability | Health food stores, specialty spice shops | Most supermarkets |
Coumarin is a natural aromatic compound that causes liver damage at high doses and has also been found to be carcinogenic in animals. The European Food Safety Authority set a tolerable daily intake of 0.1 mg of coumarin per kg of body weight.
The practical translation is more worrying than it seems:
- A person weighing 60 kg: the daily limit is 6 mg of coumarin.
- One teaspoon (2.6 grams) of cassia cinnamon contains about 5–10 mg of coumarin.
- In other words: one teaspoon of cassia cinnamon a day may reach or exceed the daily limit.
This is a conservative threshold set with a safety factor, and exceeding it occasionally is not dangerous. But anyone who takes cinnamon regularly and in a therapeutic amount — like many who try to balance their blood sugar — may exceed it over time. Isolated cases in the literature have documented reversible liver damage after taking cassia cinnamon supplements.
Practical recommendation: for everyday use in amounts from a pinch to half a teaspoon, cassia is perfectly fine. Anyone who eats a teaspoon or more of cinnamon daily, or is considering a cinnamon supplement, should switch to Ceylon cinnamon, in which coumarin is negligible. If the package does not say “Ceylon” — it is almost always cassia.
Benefits and medicinal properties
- Effect on blood sugar — the most researched benefit: meta-analyses found a drop in fasting glucose after cinnamon consumption, on the order of about 10–25 mg/dL in people with type 2 diabetes. The proposed mechanisms include slower gastric emptying, inhibition of the enzymes that break down carbohydrates in the gut, and improved sensitivity of the insulin receptor. It is important to keep this balanced: the effect on HbA1c — the measure of long-term control — was inconsistent across studies, and some studies found no improvement at all. Cinnamon is not a substitute for medication, and it is not enough on its own to control diabetes.
- Cinnamaldehyde — the main compound: responsible for the aroma and most of the biological activity, including anti-inflammatory and antimicrobial effects demonstrated in the lab.
- High antioxidant activity: one of the highest polyphenol concentrations in the food world relative to weight.
- Antimicrobial activity: cinnamon oil inhibits bacteria and fungi in the lab, and was historically used as a preservative. Its practical application in the human body is limited.
- Lipid profile: some studies showed a slight drop in LDL and triglycerides, but the findings are inconsistent.
- A practical tool for cutting added sugar: perhaps the biggest practical benefit of all — cinnamon adds a sense of sweetness to coffee, oatmeal or yogurt without a single gram of sugar.
Downsides and side effects
- Coumarin and liver toxicity: the most significant downside, as detailed above. Relevant to cassia cinnamon in regular, high intake.
- Interaction with anticoagulants: coumarin is structurally related to warfarin. Anyone taking anticoagulants should avoid large amounts of cassia and consult a doctor.
- Hypoglycemia combined with diabetes medication: because cinnamon lowers blood sugar, combining it with metformin or insulin may lower blood sugar too much. Monitoring is needed.
- Mucous membrane irritation: ground cinnamon in large amounts irritates the mouth and esophagus. The “cinnamon challenge” — swallowing a spoonful of dry cinnamon — has caused cases of aspiration, choking and lung injury, and it is dangerous.
- Allergy and contact dermatitis: cinnamon is a known allergen in the mouth, and may cause mouth ulcers and inflammation of the lips, especially from cinnamon-flavored chewing gum and toothpaste.
- Pregnancy: cinnamon in seasoning amounts in food is safe. Concentrated supplements and cinnamon oil are not recommended.
- Surgery: it is advisable to stop taking cinnamon supplements about two weeks before surgery, because of the effect on blood sugar and clotting.
Culinary use
- In coffee and hot chocolate — a pinch of cinnamon reduces the need for sugar.
- In oatmeal and yogurt — the classic combination, and especially helpful thanks to its effect on the glycemic response.
- In savory dishes — in Moroccan, Persian and Middle Eastern cooking, cinnamon seasons meat, rice and tagine. There, the spicier cassia is actually the better fit.
- Sticks vs. ground — sticks keep their aroma much longer. Ground cinnamon loses its volatile oils within months.
- Storage — in an airtight container, away from light and heat.
Summary
Cinnamon is a spice dense in polyphenols, almost completely sugar-free, with a documented effect on fasting glucose — although its effect on long-term diabetes control (HbA1c) is inconsistent, and it is in no way a substitute for medical treatment.
The practical point to take away: most cinnamon on the market is cassia, which contains coumarin in an amount that, with a daily intake of a teaspoon or more, may exceed the safe limit and burden the liver. For occasional seasoning, this is no problem. Anyone who eats a significant amount of cinnamon every day should switch to Ceylon cinnamon.
Frequently asked questions
Question: Does cinnamon contain sugar? Answer: Almost none — 0.06 grams of sugar per teaspoon (2.6 grams), which is negligible. Cinnamon is perceived as sweet because we associate its aroma with sweet pastries, but the spice itself is sugar-free. That is exactly why it is so useful: it adds a sense of sweetness to coffee, porridge or yogurt without adding sugar or calories.
Question: What is the difference between Ceylon cinnamon and regular cinnamon? Answer: Ceylon cinnamon (Cinnamomum verum) comes from Sri Lanka, has a delicate, sweet flavor, and contains a negligible amount of coumarin. Cassia cinnamon — the “regular cinnamon” in most supermarkets — is sharper and spicier, much cheaper, and contains hundreds of times more coumarin: about 2–4 mg per gram. Visually, Ceylon is a brittle multi-layered roll, and cassia is a single thick, hard bark.
Question: What are the side effects of cinnamon? Answer: The main one is a burden on the liver from coumarin, with regular intake of cassia cinnamon. Others: interaction with anticoagulants (coumarin is structurally similar to warfarin), an excessive drop in blood sugar when combined with diabetes medication, mouth irritation and ulcers, and allergic reactions. In normal seasoning amounts, cinnamon is safe for most people.
Question: How much cinnamon is safe per day? Answer: The European Food Safety Authority set a limit of 0.1 mg of coumarin per kg of body weight per day — 6 mg for a person weighing 60 kg. A teaspoon of cassia cinnamon contains about 5–10 mg of coumarin, meaning it uses up the limit. With Ceylon cinnamon, on the other hand, you can eat a teaspoon or more a day without worrying about coumarin.
Question: Does cinnamon really lower blood sugar? Answer: There is evidence of a drop in fasting glucose, on the order of 10–25 mg/dL in people with type 2 diabetes. But the effect on HbA1c — the measure of long-term control — was not found to be consistent, and some studies showed no benefit at all. Cinnamon may contribute as an addition to the diet, but it is not a substitute for medication and is not enough on its own to control diabetes.
Question: How many calories are in cinnamon? Answer: A teaspoon of ground cinnamon (2.6 grams) contains only about 6 calories, with almost no sugar. Per 100 grams there are about 247 calories, but nobody eats cinnamon in that amount.